The largest sedan in Cadillac's lineup, the 2013 XTS, handles with the poise and competence of a smaller car and with a smoothness not typically found in high-end, sporty sedans.

The modern, top-notch interior design of the XTS – complete with front seats that can have some of the biggest thigh support extenders in the business – is the best to come from Cadillac in years.

But it takes practice to use the new Cue information display with touchscreen. And even reaching over to pick up a purse that falls on the passenger-side floor can cause the radio to change channels, if only because the driver's hair accidentally brushes a display screen.

The XTS exterior is pleasing, as years of Cadillac's sharp-edge styling is smoothed for more graceful lines.

The XTS earned top, five out of five stars across the board in federal government frontal, side and overall crash test ratings.

This rating didn't take into account the fact the XTS is first with a safety alert seat that vibrates the driver's bottom if the system senses the car may be backing into an obstacle or moving into an adjacent lane that's already occupied.

Perhaps best of all, the new-for-2013, five-passenger XTS has a starting retail price of $44,995 with front-wheel drive and $51,835 with all-wheel drive. All models come with a 304-horsepower, direct-injection V-6 and six-speed automatic transmission.

Competitors include the large 2013 Lincoln MKS sedan, which has a starting manufacturer's suggested retail price, including destination charge, of $43,685 with front-wheel drive, 304-horsepower V-6 and six-speed automatic. The 2013 all-wheel drive MKS has a starting retail price of $45,680.

The 2013 Audi A6 with supercharged, 310-horsepower V-6, eight-speed automatic and all-wheel drive has a starting retail price of $51,295.

At nearly 17 feet long, from bumper to bumper, the XTS is about the same length as a Cadillac Escalade sport utility vehicle. But the XTS is longer than Cadillac's other sedans. It's10 inches longer than a 2013 CTS sedan and some 19 inches longer than the Cadillac ATS sedan.

The XTS back seat is roomy, with a full 40 inches of legroom. In the test XTS, a 5-foot-4 passenger stretched her legs easily, and a 6-footer rested comfortably. This is typically the kind of legroom found in the front seats of some sedans.

But the XTS front seats offer even more legroom – a full 45.8 inches. Seat travel fore and aft is long enough to accommodate lanky fellows as well as petite women, and thanks to a steeringwheelthat telescopes as well as tilts up and down, anyone can settle into the driver's seat nicely.

The XTS seats, themselves, were eminently supportive for long drives in the test car but didn't feel hard or overly firm. Front-seat thigh extenders are generously sized in this car, and the test Premium trim model car included heated seats in both front and back. Front seats also had fans for keeping bodies cool. All versions of XTS have leather-trimmed seats.

Fitted with Magnetic Ride Control suspension that keeps the XTS composed and the car body well managed, this sedan responds to a driver's inputs and handles with poise and grace without sending road bumps through to passengers harshly.

Some auto enthusiasts, accustomed to V-8 power, quibble whether a 3.6-liter, double overhead cam V-6 is enough for the XTS. But the test XTS performed so well on city streets and highways, with power coming on so smoothly, transmission shifts weren't noticed. Neither was the lack of a V-8.

But the direct gasoline injection of the engine gave the test XTS a lot of energetic power, and 0 to 60 miles per hour is estimated at a decent 6.5 seconds.

Thanks to all-wheel drive on the test car, engine power got to thewheelsand readily got the car going, even during rainy downpours.

The V-6 resulted in surprisingly good gasoline mileage. On a 700-mile, mostly highway trip, this large sedan averaged 24.9 miles per gallon.

Note the 4,215-pound, all-wheel drive XTS is rated by the federal government at 17 mpg in the city and 26 mpg on the highway while a front-wheel drive XTS is rated at 17/28 mpg.

A nice perk for the XTS owner: The car uses regular unleaded, not the more pricey premium gasoline that many luxury cars require.

A couple of nits: The 18-cubic-foot trunk looks impressive, but the opening is pinched by the sloping back window and much of the space is under this rear window, so upright items can be problematic. At least Cadillac provides 60/40 split folding rear seatbacks so tall things can slide through on their sides.

And, the glovebox lid in the test car always looked like it was ajar and crooked on the right side, even when it was latched.

A word of caution: The bright-colored multi displays in the XTS can be distracting, and less-than-immediate response to touches of the Cue display screen can make early working of Cue confusing.

And turned off, the display screen shows off all the fingerprints it collected.

More than 12,600 XTS cars were recalled in October because, after folding forward, the rear-seat head restraints might not lock in place in the upright position. This could result in a neck injury in a crash.